My eyesight improved radically around the middle of a 60 day mega juice fast I did under the supervision of my excellent naturopath for colon cleansing purposes. Suddenly I didn't need glasses to watch tv! I went to a movie and had to sit in the back of the theater!
I figured the change would be temporary, but two years later I finally got around to changing my prescription. Everything was all blurry with my old glasses, and I figured I needed stronger ones. Wrong! My eyes have improved by a full point.